1. Field of the Invention
Aspects of the present invention relate to a paper feeding device of an image forming apparatus. More particularly, aspects of the present invention relate to a versatile paper feeding device that can straightly feed papers without skewing when images are printed on various sizes of papers.
2. Description of the Related Art
An image forming apparatus such as a laser printer or a copier comprises a paper feeding device for feeding a print medium such as printing paper (hereinafter, paper) into the image forming apparatus body. The paper feeding device comprises a pick-up roller for picking up an individual sheet of the paper. One image forming apparatus may comprise a plurality of various kinds of feeding devices. Among the feeding devices, a versatile paper feeding device is necessitated to easily print on a small number of sheets of paper without having to open the feeding cassette, or to easily print on various sizes of paper such as an envelope or a small paper.
FIGS. 1 and 2 show the versatile paper feeding device. Referring to FIGS. 1 and 2, the versatile paper feeding device 1 comprises a pick-up roller 10, a paper support member 22 disposed under the pick-up roller 10 to stack sheets of paper thereon, a paper support expansion member 21 formed to be capable of freely sliding toward the paper support member 22 to support the paper, and a paper alignment member 23 formed on the paper support member 22 to align the paper. The versatile paper feeding device 1 may be formed on a side cover frame 40 of the image forming apparatus. In the versatile paper feeding device 1, as signals are transmitted to the image forming apparatus, a rotative shaft 12 is rotated by a driving device (not shown) and the pick-up roller 10 is simultaneously rotated so that the paper S is moved in direction A of FIG. 2 and fed to the next step, i.e., a feeding roller (not shown) one at a time. As the versatile paper feeding device 1 prints on paper with a relatively greater size in a lengthwise direction such as letter, A4 or legal size, sufficient area for supporting the paper S cannot be obtained by using only the paper support member 22. Therefore, the paper support expansion member 21 is extended so that sufficient area for supporting the paper S in a lengthwise direction is obtained and then the paper S is put thereon. Additionally, as the paper S is advanced in direction A for printing an image thereon, the paper alignment member 23 formed on the paper support member 22 is properly adjusted in an arrow direction BC to constrain the paper S from moving in a widthwise direction.
However, the conventional versatile paper feeding device 1 has the paper alignment member 23 formed only on the paper support member 22 of the leading end of the paper but has no separate paper alignment member on the paper support expansion member 21 of the following end of the paper. Therefore, as the versatile paper feeding device 1 prints on a paper with a relatively greater size in a lengthwise direction such as letter, A4 or legal size, the following end of the paper S is free to move in arrow direction DE, while the paper S is fed through the pick-up roller 10 to the feeding roller (not shown), such that a skew occurs. When the paper S with a skew is fed to the feeding roller, the image is skewed as much as the paper S is skewed, and further, a jam may occur.